A recent study showed that beta-carotene supplements could be useful in the prevention of recurrent colon polyps in teetotalers and non-smokers. In this study, more than 500 people were given either beta-carotene or placebo, along with vitamins C and E.
The group taking Beta-carotene resulted in a 44 percent decrease in new polyps formation. However, this benefit was not apparent in people who drank alcohol or smoked during the study.
This clearly indicates that smoking or drinking interferes with benefits of beta-carotene. The results also indicate that there is a possibility of interaction between other dietary factors like high fat diets, caffeine intake, sedentary life style with beta-carotene and other antioxidants. However, other studies are also consistently showing the benefits of consuming fruit and vegetables (rich sources of beta carotene) with respect to less cancer incidences and better health.